Ultrasonic control of bolt tightening
US7360435B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2005 |
| Grant date | Apr 22, 2008 |
| Priority date | — |
| Expiry date | Aug 20, 2026 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B2031/022
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Tightening of a bolt is controlled by monitoring the change in round trip time of propagating longitudinal ultrasonic waves through the bolt and the reflection of these waves at the end of the bolt. The round trip time of the longitudinal waves through bolt is continuously measured and monitored in real-time. Elongation of the bolt as it is being tightened is determined based on the change in the round trip time of the longitudinal waves, which provides the level of bolt tension and joint clamp load. In determining the bolt elongation, an elongation-dependent wave speed has been formulated and used in-real time. When the elongation of the bolt reaches a predetermined level, tightening is automatically stopped.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.